Method for locating tracts of electrical brain activity

Abstract

A method and apparatus for locating tracts of electrical brain activity. A source localization procedure may be performed including solving the inverse problem subject to one or more constraints resulting from a tractographic procedure, and a tractographic procedure may be performed that includes obtaining a probabilistic assessment of tract connectivity that takes account of the results of a source localization procedure.

Description

FIELD OF THE INVENTION[0001]The present invention relates to a method for locating tracts of electrical brain activity, and more particularly relates to synergistic use of EEG and tractography for this purpose.BACKGROUND OF THE INVENTION[0002]For many purposes, such as evaluating the brain's health or understanding its operation, it is important to identify those portions of the brain which are, at a particular time or in response to a particular stimulus, active, as distinct from other portions of the brain which are not.[0003]Brain activity is characterized by chemical reactions in brain cells, the chemical reactions generating electrical current and the electrical current being transmitted to other brain cells through nerve fibers, or “tracts” that establish a communication network. Therefore, characterizing the manner in which brain activity is integrated over regions of cortex could be described as determining the specific tracts that are active.[0004]When a tract is active, i....

AI Technical Summary

Benefits of technology

[0018]According to an iterative aspect of the invention, the method may further include performing a second tractographic analysis indicating a second probability that at least two second sources of the model sources are connected by one or more second tracts, the second probability taking account of at least one of the solutions. Preferably, the second probability takes account of a covariance of the second sources established in at least one of the solutions.

[0019]According to another aspect of the invention, a representative method includes performing a first EEG procedure on the brain, including obtaining one or more first solutions to a first inverse problem relating source and measured potentials, and performing a tractographic analysis of the tracts, wherein the tractographic analysis indicates a first probability of the connectivity of at least two tracts taking account of the first solution.

[0020]Preferably, the method includes identifying a cortical surface of the brain, and virtually disposing first model sources on the cortical surface. The tractographic analysis identifies ends of the tracts, and the method preferably further includes aligning the ends with the cortical surface and thereby identifying surface regions of the cortical surface associated with the aligned ends. Preferably, the method still further includes associating the aligned ends with the first model sour...

Problems solved by technology

More particularly, it is common that more than one tract trace through the same voxel, and tractography does not have the resolution to establish which is which.

It is, however, a substantial drawback of the method that the result is probabilistic, not deterministic.

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